Is it possible for an oqb-dl ef 2k2,p0;;sj nmfvt2ubject moving with a constant speed to accelerate? Explainv2ffmjdn ;t b;2eslu0 , kq2p-.

  Consider a particle moving with constant speed such tq12h -v9+r/xf/ jk l fiw;vamihat its acceleration of constant magnitude is always perpendicular to its ve // j;qw kxiim1f2frha-l+v 9vlocity.

  An object moves in a circular path at a cs7 l7wl;xc w6p6xo+ 0 *khguoconstant speed. Compare the direction of the uk*cx6l xw670s7hwc; po o+globject's velocity and acceleration vectors.

  When an object experiences uniform circular motion, the direction of the accelels-e* xja)cf1rl)*sa1ecx-f jation is

  Consider a particle moving with constant speg.o1w sn+ uy3 seut+ z6p9j.ased such that its acceleration of constant magnitude is always perpendicular to 6 w3atus+nos+ z9g e1ypus..j its velocity.

  What type of acceleration does an object moving with con, 3zgkp 0tlppjy8(;zvstant speed in a circular pl0zz t8ky ,g;3j( pvppath experience?

  What force is needed to o2qpd0 5((t d 0z3c .yyoh:vv5r bp 6rqny)goxmake an object move in a circle?

  When an object experiences uniform circulacu2iinz35+o/-c x eo ubony*7 r motion, the direction of the net for 5ib-/unuc *3ioyon7+ze2 ocxce is

  A roller coaster car io0 sps8v:+vfr o q.aw-s on a track that forms a circular loop in the vertical plane. If the car is to just maintain contact with track at the top oa :qoo8.s+-sfvv0pw r f the loop, what is the minimum value for its centripetal acceleration at this point?

  A roller coaster car (mass = M) is on a track that forms a circular l /db3zoe+9dt ooop (radius = r) in the vertical plane. If the car is to just maintain contac3d9z bo/+td eot with the track at the top of the loop, what is the minimum value for its speed at that point?

  A pilot executes a vertical dij kroj d /u*j2xng7*z*ve then follows a semi-circular arc until it is going straight up. Just as the plane is at its lowest po* uojjdjrz*xg k*2n /7int, the force on him is

  A coin of mass $m$ rests on a turntable a distance $r$ from the axis of rotation. The turntable rotates with a frequency of $f$. What is the minimum coefficient of static friction between the turntable and the coin if the coin is not to slip?

  A car goes around a cury lib 0t9ksc3iy)uahwr;j45(ve of radius $r$ at a constant speed $v$. What is the direction of the net force on the car?

  A car goes around a curve of radius r at a con)7 it5/ pqbhb8ogjw-4 uabl/lstant speed v. Then it goes around the same curve at half of the original speed. What is the centripetal force on the car as it goes around the curve jlwbui) 45a8/7-lpg hbq/ tbo for the second time, compared to the first time?

  A car goes around a cz3gxc ae4*k1wg+t0w f urve of radius r at a constant speed v. Then it goes around a curve of radius 2r at speed 2v. What is the centripetal force on the car as it goc* g314kf wa zg+txew0es around the second curve, compared to the first?

  A car of mass m goes around a banked curve of ebsw1 ofpv 0:,radius r with speed v. If the road is frictionless due to ice, the car can still negotiate the curve if the horizontal component of the normal forc 0eobs,pf1:vw e on the car from the road is equal in magnitude to

  Two horizontal curves on a bobsled run are banked at the same angle, bb4sz rp 7.3xrcut one has twice the radius of the other. The safe speed (no friction needed to stay on the run) for the smaller radius curve is v. What is the safe speed on the larger ra r .x3cpr4zsb7dius curve?

  The banking angle inn.pbi5 28il8)djho rey+0i bk a turn on the Olympic bobsled track is not constant, but increases upward from the horizontal. Coming around a turn, the bobsled team will intentionally "climb the wall," then go lower coming out of the turn. Why do they do ji . l ky8b +ih5p0ined8b)o2rthis?

  Is it possible for an object moving around )/3cn -zqnch mbp;p r1a circular path to have both centripetal and tangential acceleration? 3m) phcbnz -;1pcnqr/

  The gravitational force between two object8m x2u+r vn4rps is proportional to

  The gravitational force between two objects is i2lug0w2k ;fj1v. b p1i lkrzxf3c)gvf88d: s bnversely proportional to

  Two objects attract each other gravitatiojg 81s1few.zxhusru7ww6h b8 -wy,8c nally. If the distance between their centers is cut in half, the gravitational8 syhwe1ww ,j6g-uh.8 c wfz18bx7 urs force

  Two objects, with massesbz,0 t.z1bmm g $m_{1}$ and $m_{2}$, are originally a distance r apart. The gravitational force between them has magnitude F. The second object has its mass changed to 2$m_{2}$, and the distance is changed to r/4. What is the magnitude of the new gravitational force?

  Two objects, with massedr iut:+eec w d)2;jw/s $m_{1}$ and $m_{2}$, are originally a distance r apart. The magnitude of the gravitational force between them is F. The masses are changed to 2$m_{1}$ and 2$m_{2}$, and the distance is changed to 4r. What is the magnitude of the new gravitational force?

State Newton's law of universal s,d:f o;c(ze)1xm7*ujcch.gco jfn /gravitation.

  Compared to its mass on the Earth, the mass of an object on thpxum.dahf + ),e Moon is

  The acceleration of gravityz fftnu9d97 n4c 2l.wr on the Moon is one-sixth what it is on Earth. An object of ma9n4wdfr czl n .7uft92ss
72 kg is taken to the Moon. What is its mass there?

  As a rocket moves away from the Earth's su-o o*7xa fj7fgrface, the rocket's weight

  A spaceship is traveling to the Moon. At wha gx;pk;t nm gau, i59go16juz1t point is it beyond the pull of Earth 51; ,g o;iut gjpnkz1gaxm6u9's gravity?

  Suppose a satellite were orbiting the Earthuiudg8old8,q) u (u 8 wq+8fpbbt0 hc1 just above the surface. What is its centripetal accw8 tio gd8f)p8c8h+b1u d,0qubq ulu(eleration?

  A hypothetical planet has a mass of half that oxz )/ugra; 6lof the Earth and a radius of twice that of the Earth. What is the acceleration due to gravity o r;z x6)/lgaoun the planet in terms of g, the acceleration due to gravity at the Earth?

  The acceleration of gravity on the Moon is one-sixtv ytedc9169-j4 iptz vh what it is on Earth. The radius of the Moon is one-fourth that of thed e-t9z iycptvj4 916v Earth. What is the Moon's mass compared to the Earth's?

  Two planets have the same surface lca cm.1zz,ot.i j0(q gravity, but planet B has twice the radius of planet A. If planet A has mass m, what is the mass of plaz c(1qcl,ioatz j ..m0net B?

  Two planets have the same surface gravity, but planet B has twice the . rj*:gvlvjr t: ,+i ;kkyp6nv+tul)gmass of planet A. If planet A has radius r, what it ; :p g gv,yn)6:tvrlkj.kril+ juv+*s the radius of planet B?

  Consider a small satellite moving in a circular orbit (radius r) ab )nmn0bgv2 yzt tnq5wao10l;;out a spherical planet (mass M). Which expression gives o1n00lwq5vm)t t ba;2 gny;n zthis satellite's orbital velocity?

  Satellite A has twice the mass of satellite B, and rotates in th*1y;oof kpi4eix 26 mie same orbit. Compare ioei6ky1fpi; o24x*m the two satellite's speeds.

  A person is standing on a scale in an elevator accelerating downwaru8/ jzud*heh .d. Compare the readinu/.eh8d zh *ujg on the scale to the person's true weight.

  Who was the first person hsu)9 m+ gpil0rl u7d*to realize that the planets move in elliptical paths aroug0)p rld+7lu i *su9hmnd the Sun?

  The speed of Halley's Comet, while ti s ifn:/39y:w 2n rckh xog416gsco.oraveling in its elliptical orbit around the Sun,4gc o:fysno:6x s3hi/w .kcrg2i9n1o

  Let the average orbital radius of a planet be R. Let the orbital period be T. s/vo22gqj m0rWqsrmo j v/20g2hat quantity is constant for all planets orbiting the Sun?

  A planet is discovered to orbit around a star in the galfohxty,+q w l v*y/e j8im;3j.axy Andromeda, with the same orbital diameter as the Earth around our Sun. If that star has 4 times the mass of our Sun, what will the period of revolution of that new planet be, compared to the Earth's or/y.ly jei +qw*jo8tx,3 hv;fmbital period?

  The average distance from the Earth to the Sun is defined as one "0 cvwrw.7e8h 2 ssyu2oastronomical unit" (AU). An asteroid orbits r.c os 207es8 h2uwwvythe Sun in one-third of a year. What is the asteroid's average distance from the Sun?

State Kepler's laws.ld) ;k o:wo ms4yzgurhg 8s(3)

  List the four fundamental forces in nb3 /a69:rbuhw 6e bx/rxi p3ueature.

  An object moves with a constant speed of 30 m/l./u *hr 7,jwuse9 gles on a circular track of radius 150 m. What is the acceleration of tr 9wh.*l7, eu gjs/leuhe object?

  The maximum speed around a level curve is 30.0 km/h. What is the maximu4dq 9;v a:zavmm speed around a curve with twice the radiusz4av ;vmda9 :q? (Assume all other factors remain unchanged.)

  What is the centripetal acceleration of a point oi+)h;trwx :uv n the perimeter of a bicycle wheel of diameter 70 cm wi:;vrhwuxt +)hen the bike is moving 8.0 m/s?

  A point on a wheel rotating at 5.00 rev/s is located 0.200 m from the. dh-h(q3 xbdt9m g+wchbi9g0 axis. What is the centripetal acceler9dc30.+d x9 b t-gmwq(ihbg hhation?

  How many revolutions per minute must a circular, rotating space station of ra1 e+m5kyn0x fsy3( li3yj;zk ol 2i2xndius 1000 m rotate to produce an arnmlf3snki;x x2+e15 0y2 jyi(lzoy k3tificial gravity of $9.80 \; m/s^2$?

  A motorcycle has a mass of 250dv n :lt0p;pw;lk/qc j*g( e: s4vow;g kg. It goes around a 13.7 m radius turn at 96.5 km/h. What is the centripetal force on the mo(:twsgp /ncolwv;qkg ; ;*:eplj0v4d torcycle?

  A 0.50-kg mass is attached to the end of a 1.0-m string. Thl/ux/4cjl :eye system is whirled in a horizontal circular path. If the maximum tension that the string can withstand is 350 N. What is the maximum speed of the mass if the string is not clj4ul: / exy/to break?

  A stone, of mass m, is attached to a strong string and whirledjyij4m5d0+, za m (clv ona bn*.y(6dt in a vertical circ 6amt(40ynabl i* mj.dc5 +ojv dn(,yzle of radius r. At the exact top of the path the tension in the string is 3 times the stone's weight. The stone's speed at this point is given by

  A stone, of mass m, is attached to a strong stringv;o7wutt 1mbi*q: 1 m-+ mseqzsfu.s8 and whirled in a vertical circle of radius r. At the exact bottom of the path the tension in the string is 3 times the stone's weight. The stone's speed at this point is given szbvmt8sm 1wu*-. e1mtq q 7o:si;uf +by

  A jet plane flying 600 m/s experiences an acceleration of 4kf)rf ,sbb/ h)g when pulling out of the dive. What is the radius of curvature of the loop in r)/)fhsk ,fbb which the plane is flying?

  A pilot makes an outside vertical loop (in which the center ofdb q0r;.1nshesy26y f the loop is beneath him) of radius 3200 m. At the top of his l y6rq .d0hsfy2 1ns;eboop he is pushing down on his seat with only one-half of his normal weight. How fast is he going?

  The maximum force a y ae/j;03ryrm f-u.yjpilot can stand is about seven times his weight. What is the minimum radius of curvature that a jet y3jjr r m0fy/u;y- e.aplane's pilot, pulling out of a vertical dive, can tolerate at a speed of 250 m/s?

  A car traveling 20 m/s rounds an 80-m radius horizontal curve with tvoh2 e) 3mo5vlhe tires on the verge of slipping. How fast can this car round a second curve of radius 320 m? (Assume the same coefficient of friction between the car'solv m5he2)3o v tires and each road surface.)

  A car is negotiating a flat curve of ra 4u5pwg8vqoh;dius 50 m with a speed of 20 m/s. The centripetal force provided by fw vghup 4qo;85riction is $1.2 \times 10^{4} \; N$. What is the mass of the car?

  A car goes around a flat curve of ; ss* 6k-/0xyvu x*xglkht/waradius 50 m at a speed of 14 m/s. What must be the minimum coefficient of friction between the tires and the road for* ys w /-/u s6x;kkl*ht0axvgx the car to make the turn?

  A car is moving with a constant speed v around a level curve.eg)jl :tq( 79 kzzfhg; The coefficient of friction between the tires and the road is 0.40. What is the minimum radius of the curve g)z;ejgt hzl7 q(:f9 kif the car is to stay on the road?

  What minimum banking angle is requir+lq fg5j d8qr5ed for an Olympic bobsled to negotiate a 100-m radius turn at 35 m/s withou55+q gqrl8jdft skidding? (Ignore friction.)

  A horizontal curve on a bobs6jvrvg o(exlm/0 u4 5wled run is banked at a $45^{\circ}$ angle. When a bobsled rounds this curve at the curve's safe speed (no friction needed to stay on the run), what is its centripetal acceleration?

  A frictionless curve of radius 100 m, banked at an angle of ci*3adhytxy 1sob+fr 9 83 /qm$45^{\circ}$, may be safely negotiated at a speed of

  A curve of radius 80 m is bank hsl (ssksm/r55b5;l:3m ugx ved at $45^{\circ}$. Suppose that an ice storm hits, and the curve is effectively frictionless. What is the safe speed with which to take the curve without either sliding up or down?

  A 175-kg ball on the end of ztto b+ 6d2fv0*4p; gpzhg7 hqa string is revolving uniformly in a horizontal circle of radiu*z p+doftq67bhtv2gg0 ph4 ;zs 0.500
m. The ball makes 2.00 revolutions in a second. (only fill in numerial value in the blanks)
(a) Determine the speed of the ball.    $m/s$
(b) Determine the ball's centripetal acceleration.    $m/s^2$
(c) Determine the force a person must exert on opposite end of the string.    $N$

  Starting from rest in the pit area, a race car accelerates at a uniform ra,4 8+x hh)lohflr nlw5e;1p pvku08 dite to a speed ok u+ihxdhl; lo5wr8nep)fl ,04 18hpv f 45 m/s in 15 s, moving on a circular track of radius 500 m. (only fill in numerical value in the blanks)
(a) Calculate the tangential acceleration.    $m/s^2$
(b) Calculate the radial acceleration when the instantaneous speed is equal to 30 m/s.    $m/s^2$

  The hydrogen atom consists of a proton of masl p42q3/ sb jwwtpi)x8t:i1qb s $1.67 \times 10^{-27} \; kg$ and an orbiting electron of mass $9.11 \times 10^{-31} \; kg$. In one of its orbits, the electron is $5.3 \times 10^{-11} \; m$ from the proton. What is the mutual attractive force between the electron and proton?

  What is the gravitational force on a 70-kg person sta tk qme(/d:*44qvcqfqqpqs1* nding on the Earth, due to the Moon? Thq: qd4mv fekqs(p/ 41*qqqtc*e mass of the Moon is $7.36 \times 10^{22} \; kg$ and the distance to the Moon is $3.82 \times 10^{8} \; m$.

  The gravitational attractive force between tw a i2,tw4oi*zjo masses is F. If the masses are moved to half of their initial distance, i*,j4w oi taz2what is the gravitational attractive force?

  For a spacecraft going from the Earth toward the Sun, at what di+f qj.w;f1 chzddn4jhb 1,8ihstance from the Earth will the gravitational forces due to the Sun ; ,8dcw1jf+4hz. fb iqd1nh hjand the Earth cancel?
Earth's mass: Me = $5.98 \times 10^{24} \; kg$ the Sun's mass: Ms = $1.99 \times 10^{30} \; kg$
Earth-Sun distance: r = $1.50 \times 10^{11} \; m$

  The mass of the Moon d) 5wo4t5th;jf3 l1 dx+nyjusis $7.4 \times 10^{22} \; kg$ and its mean radius is $1.75 \times 10^{3} \; km$. What is the acceleration due to gravity at the surface of the Moon?

  An astronaut goes out ford0m70 e 86lz pku,yslt a "space-walk" at a distance above the Earth equal to the radius of the Ear,7 8ktmep0 s yud60llzth. What is her acceleration due to gravity?

  The radius of the Earth is R. At what distance above t9 ;-ja6tbgu *g5ej;mem3y mgl he Earth's surface will the acceleration of gravm uy;g;5m3a9me jb6-g *tg jelity be $4.9 \; m/s^2$?

  A satellite encircles Mars at a dist7;7 an*ncohyyance above its surface equal to 3 times the radius of Mars. The acceleration of gravity of the satellite, as compared to the acceleration of gravity on the surface 7cnnh7yay*o; of Mars, is

  At a distance of 14000 km from some planet's center, the acerr (11y5jrry6gz gn *celeration of gravity i5 1 gryjg1ry(nrr6ze *s $32 \; m/s^2$. What is the acceleration of gravity at a point 28000 km from the planet's center?

  An object weighs 432 N b+ 4akf (wddwcq4; azg2 0jhp6on the surface of the Earth. The Earth has radius r. If the object is raised to a height of 3r abovwjca2 qddp;a w k6(zhgb+f 044e the Earth's surface, what is its weight?

  By how many newtons does the weight of a 100-kg person change when hl ;x3p ruxy28h ex8)ime goes from sea level to an altitude of 50 hx ;8p8 yerxiul2)xm300 m? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  The Earth has radius r. A satellite of mass 100 kg is at 4p8,guj ojf smnb4ipcvxi uf5/9 0o/ -a point 3r above the Earth's ocfgus-0 j4fp5 v/mixu9jp bo,n i/48surface. What is the satellite's weight?

  A spherically symmetric planet hec5 xbvkr x, hy ,wb8r4y1m/0bas four times the Earth's mass and twice its radius. If a jar of peanut butter wecr4vmx bhy b18y w ,/5bk,r0xeighs 12 N on the surface of the Earth, how much would it weigh on the surface of this planet?

  During a lunar eclipse, the Moon, Earth, and Sun all lie on the same line, w, wj, omvz0k u7..ykxcith the Earth between the Moon and the Sun. .jxzk0 u.m c7,,vowky The Moon has a mass of $7.36 \times 10^{22} \; kg$; the Earth has a mass of $5.98 \times 10^{24} \; kg$; and the Sun has a mass of $1.99 \times 10^{30} \; kg$. The separation between the Moon and the Earth is given by $3.84 \times 10^{8} \; m$; the separation between the Earth and the Sun is given by $1.496 \times 10^{11} \; m$.
(a) Calculate the force exerted on the Earth by the Moon, its magnitude is    $\times 10^{20} \; N$, its direction is  ----待选择----towardsaway from  the moon.
(b) Calculate the force exerted on the Earth by the Sun, its magnitude is    $\times 10^{22} \; N$, its direction is  ----待选择----towardsaway from  the Sun.
(c) Calculate the net force exerted on the Earth by the Moon and the Sun, its magnitude is    $\times 10^{22} \; N$, its direction is  ----待选择----towardsaway from  the Sun.

  A 2.10-kg brass ball is trf 8wt0c*9nmv oansported to the Moon.
(a) Calculate the acceleration due to gravity on the Moon.    $m/s^2$ (The radius of the Moon is $1.74 \times 10^{6} \; m$ and the mass of the Moon is $7.35 \times 10^{22} \; kg$)
(b) Determine the mass of the brass ball on the Earth    $kg$ and on the Moon    $kg$
(c) Determine the weight of the brass ball on the Earth    $N$
(d) Determine the weight of the brass ball on the Moon    $N$

  A satellite is in a low circular orbit about the Earth (i.e., kzw(-fp w5b v-i.+e uko12 ksnit just skims the surfai1k2w v pkns-zb( -w f5+e.uokce of the Earth). What is the speed of the satellite? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in a low circular orbit about the Earth (i.e., it just skimsq*,(t-dc d kfu)w/zl2ia; eel the surface of the Earth). How long does i fw-l itz, ead(lduq/*c e2k);t take to make one revolution around the Earth? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  A satellite is in circular orbit 230 km abov iif,yy6)r)h,;qsn k 3f 6grrwe the surface of the Earth. It is observed to have a period of 89 min. What is the mass of the Earthn ,r;k 6riy 3s))fq f6ygiwr,h? (The mean radius of the Earth is $6.38 \times 10^{6} \; m$.)

  Europa, a moon of Jupiter, has an orbital dim(g2d *uru a-cx rz.g5ameter of $1.34 \times 10^{9} \; m$, and a period of 3.55 days. What is the mass of Jupiter?

  The innermost moon of Jupiter orb-fjo x)7y .-s.qgovg mits the planet with a radius of $422 \times 10^{3} \; km$ and a period of
1.77 days. What is the mass of Jupiter?

  Two moons orbit a planet in+ c;wdf(hij4 g nearly circular orbits. Moon A has orbital radius r, and moon B has orbital radius 4r. Moon A takes 20 days to complete one orbit. How long does it take moon B to ci(df h+;w4gj complete an orbit?

  The planet Jupiter is pm7sru1ft*i 6$7.78 \times 10^{11} \; m$ from the Sun. How long does it take for Jupiter to orbit once about the Sun? (The distance from the Earth to the Sun is $1.50 \times 10^{11} \; m$.)

  It takes the planet Jupiter 12 years to el9 bb8o;1uhfl3-g qu orbit the Sun once. What is the average distance fl-bo9fh3l ue 1buqg 8;rom Jupiter to the Sun? (The distance from the Earth to the Sun is $1.5 \times 10^{11} \; m$.)